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v3.19.1

Credit and Other Debt Agreements - Summary of Corporate and Other Debt (Parenthetical) (Detail) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2019 | Dec. 31, 2018
Premium Financing Debt Facility [Member] |  |
Debt Instrument [Line Items] |  |
Periodic payments of interest and principal, expiry date | 2020 | 2020
Fixed Rate of 3.20%, Balloon Due June 24, 2019 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 3.20% | 3.20%
Periodic payments of interest and principal, expiry date | 2019 | 2019
Fixed Rate of 5.85%, balloon Due November 30, 2019 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 5.85% | 5.85%
Periodic payments of interest and principal, expiry date | 2019 | 2019
Fixed Rate of 3.48%, Balloon Due June 24, 2020 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 3.48% | 3.48%
Periodic payments of interest and principal, expiry date | 2020 | 2020
Fixed Rate of 3.99%, Balloon Due July 10, 2020 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 3.99% | 3.99%
Periodic payments of interest and principal, expiry date | 2020 | 2020
Fixed Rate of 5.18%, Balloon Due February 10, 2021 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 5.18% | 5.18%
Periodic payments of interest and principal, expiry date | 2021 | 2021
Prime or LIBOR Plus up to 1.45%, Expires April 8, 2021 [Member] | Credit Agreement [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 1.45% | 1.45%
Periodic payments of interest and principal, expiry date | 2021 | 2021
Fixed Rate of 3.69%, Balloon Due June 14, 2022 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 3.69% | 3.69%
Periodic payments of interest and principal, expiry date | 2022 | 2022
Fixed Rate of 5.49%, Balloon Due February 10, 2023 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 5.49% | 5.49%
Periodic payments of interest and principal, expiry date | 2023 | 2023
Fixed Rate of 4.13%, Balloon Due June 24, 2023 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 4.13% | 4.13%
Periodic payments of interest and principal, expiry date | 2023 | 2023
Floating Rate of 1.65% LIBOR Plus Balloon Due August 2, 2023 [Member] |  |
Debt Instrument [Line Items] |  |
Quarterly payments of interest rate | 1.65% | 1.65%
Periodic payments of interest and principal, expiry date | 2023 | 2023
Quarterly payments of interest, description | 90 day LIBOR plus | 90 day LIBOR plus
Fixed Rate of 4.72%, Balloon due February 13, 2024 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 4.72% | 4.72%
Periodic payments of interest and principal, expiry date | 2024 | 2024
Fixed Rate of 4.58%, Balloon Due February 27, 2024 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 4.58% | 4.58%
Periodic payments of interest and principal, expiry date | 2024 | 2024
Floating Interest Rate of 1.40% LIBOR Plus Balloon Due June 13, 2024 [Member] |  |
Debt Instrument [Line Items] |  |
Quarterly payments of interest rate | 1.40% | 1.40%
Periodic payments of interest and principal, expiry date | 2024 | 2024
Quarterly payments of interest, description | 90 day LIBOR plus | 90 day LIBOR plus
Fixed Rate of 4.31%, Balloon Due June 24, 2025 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 4.31% | 4.31%
Periodic payments of interest and principal, expiry date | 2025 | 2025
Fixed Rate of 4.85%, Balloon due February 13, 2026 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 4.85% | 4.85%
Periodic payments of interest and principal, expiry date | 2026 | 2026
Fixed Rate of 4.73%, Balloon Due February 27, 2026 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 4.73% | 4.73%
Periodic payments of interest and principal, expiry date | 2026 | 2026
Fixed Rate of 4.40%, Balloon Due June 2, 2026 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 4.40% | 4.40%
Periodic payments of interest and principal, expiry date | 2026 | 2026
Fixed Rate of 4.36%, Balloon Due June 24, 2026 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 4.36% | 4.36%
Periodic payments of interest and principal, expiry date | 2026 | 2026
Fixed Rate of 4.09%, Balloon Due June 27, 2027 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 4.09% | 4.09%
Periodic payments of interest and principal, expiry date | 2027 | 2027
Fixed Rate of 4.09%, Balloon Due August 2, 2027 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 4.09% | 4.09%
Periodic payments of interest and principal, expiry date | 2027 | 2027
Fixed Rate of 4.14%, Balloon Due August 4, 2027 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 4.14% | 4.14%
Periodic payments of interest and principal, expiry date | 2027 | 2027
Fixed Rate of 3.46%, Balloon Due December 1, 2027 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 3.46% | 3.46%
Periodic payments of interest and principal, expiry date | 2027 | 2027
Fixed Rate of 4.55%, Balloon Due June 2, 2028 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 4.55% | 4.55%
Periodic payments of interest and principal, expiry date | 2028 | 2028
Fixed Rate of 4.34%, Balloon due June 13, 2028 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 4.34% | 4.34%
Periodic payments of interest and principal, expiry date | 2028 | 2028
Fixed Rate of 5.04%, Balloon due February 13, 2029 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 5.04% | 5.04%
Periodic payments of interest and principal, expiry date | 2029 | 2029
Fixed Rate of 4.98%, Balloon Due February 27, 2029 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 4.98% | 4.98%
Periodic payments of interest and principal, expiry date | 2029 | 2029
Fixed Rate of 4.19%, Balloon Due June 27, 2029 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 4.19% | 4.19%
Periodic payments of interest and principal, expiry date | 2029 | 2029
Fixed Rate of 4.19%, Balloon Due August 2, 2029 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 4.19% | 4.19%
Periodic payments of interest and principal, expiry date | 2029 | 2029
Fixed Rate of 4.44% Balloon Due June 13, 2030 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 4.44% | 4.44%
Periodic payments of interest and principal, expiry date | 2030 | 2030
Fixed Rate of 5.14%, Balloon due March 13, 2031 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 5.14% | 5.14%
Periodic payments of interest and principal, expiry date | 2031 | 2031
Fixed Rate of 4.70%, Balloon Due June 2, 2031 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 4.70% | 4.70%
Periodic payments of interest and principal, expiry date | 2031 | 2031
Fixed Rate of 4.34%, Balloon Due June 27, 2032 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 4.34% | 4.34%
Periodic payments of interest and principal, expiry date | 2032 | 2032
Fixed Rate of 4.34%, Balloon Due August 2, 2032 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 4.34% | 4.34%
Periodic payments of interest and principal, expiry date | 2032 | 2032
Fixed Rate of 4.59% Balloon Due June 13, 2033 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 4.59% | 4.59%
Periodic payments of interest and principal, expiry date | 2033 | 2033
Fixed Rate of 5.29%, balloon due March 13, 2034 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 5.29% | 5.29%
Periodic payments of interest and principal, expiry date | 2034 | 2034
Fixed Rate of 4.69% Balloon Due June 13, 2038 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 4.69% | 4.69%
Periodic payments of interest and principal, expiry date | 2038 | 2038
Fixed Rate of 5.45%, balloon due March 13, 2039 [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 5.45% | 5.45%
Periodic payments of interest and principal, expiry date | 2039 | 2039
Facility B [Member] | Interbank Rates Plus 1.05% Expires May 18, 2020 [Member] | Premium Financing Debt Facility [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 1.05% | 1.05%
Facility C and D [Member] | Interbank Rates Plus 1.05% Expires May 18, 2020 [Member] | Premium Financing Debt Facility [Member] |  |
Debt Instrument [Line Items] |  |
Periodic Payment of Interest | 0.55% | 0.55%

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